(1) Field of the Invention
The present invention relates to a contact of an electric connector, more especially to a contact of a connector suitable for connecting a flat flexible film printed circuit board.
(2) Description of the Prior Art
In the recent development of the miniaturization of the electronics parts, the flexible wiring system using a flat flexible film printed circuit board has become more and more popularly used for interconnecting the devices in electronic equipment.
In such a flexible wiring system, it is popular to arrange at least one end of such a flat flexible film printed circuit board to act as a male contact member. The male contact member formed at one or both ends of the flat flexible film printed circuit board generally comprises a number of male contact elements provided by a printed wiring technique such as applying copper foil or applying etching if required. The male contact elements are arranged in parallel rows spaced equidistantly. The male contact member is inserted into a female contact member provided on the equipment side. The female contact member is generally formed as a multi-contact member having a number of female contact elements. The female contact elements are connected by wiring to desired electronic devices.
The flat flexible film printed circuit board is very thin and hence it has less stiffness. Accordingly, for a large numbered multi-contact member, such as for example of 20 or more terminals, difficulty arises when inserting the male contact member formed by the flexible film circuit board into a female connector member.
It is known to provide a lining at the terminal portion of the flexible film printed circuit board using, for instance, a polyester plate to make the thickness of the contact portion thereof larger to attain an easy insertion.
This practice has, however, a disadvantage in that a large force is required when disengaging the connection when the connection needs to be disconnected, for instance, at some maintenance purpose. The increase of pulling force at disengagement of the connector is very high and is much higher than ordinarily expected due to increase of the contact pressure. The increase of pulling off force of the connector member may reach 3 to 4 times the former value when such lining is not used. By reason of such high pulling off force when the connector member is desired to be disengaged not only uneasiness of handling results, but in some occasion the flat flexible film printed circuit board may be torn or damaged.